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name: test-model description: Validate model correctness using MCP tools. Checks element references, relationships, view definitions, and syntax.

Test LikeC4 Model

Use this skill when validating LikeC4 model correctness and integrity.

Validation Workflow

1. Project Structure Validation (REQUIRED)

Use LikeC4 MCP read-project-summary to validate:

• All element kinds are defined in shared specifications
• All relationship kinds exist in spec files
• Tags are properly declared
• No orphaned elements

2. Element Reference Validation (REQUIRED)

Use LikeC4 MCP search-element to verify:

• All referenced elements exist
• FQN usage is correct for nested elements
• instanceOf references point to valid Containers

3. Relationship Validation (REQUIRED)

Use LikeC4 MCP find-relationships to check:

• Relationships use valid typed kinds
• No duplicate relationships between same elements
• All relationships have descriptive labels
• No reverse/return relationships exist

4. View Validation (RECOMMENDED)

Use LikeC4 MCP open-view to preview:

• Views render correctly without errors
• Include patterns show expected elements
• Layout hints (rank source/sink) work as intended
• No unexpected elements appear due to over-broad wildcards

5. Syntax Validation (RECOMMENDED)

Use Context7 MCP query-docs to verify:

• Relationship syntax is correct
• View syntax follows LikeC4 DSL standards
• Deployment instanceOf syntax is proper

Common Issues to Check

Broken References

Copy# Use LikeC4 MCP search-element to find elements
# Verify all referenced elements exist in model

Invalid Element Kinds

Copy# Use LikeC4 MCP read-project-summary
# Check that all element kinds are in spec-*.c4 files

Missing Relationship Labels

Copy❌ api -[calls]-> service          // Missing label
✅ api -[calls]-> service 'Fetches data'

Over-broad View Includes

Copy❌ include **                      // Too broad
✅ include mySystem.*              // Scoped

Testing Checklist

• Run LikeC4 MCP read-project-summary - verify all element kinds exist
• Search for all FQN references - use search-element to validate
• Check relationships - use find-relationships for key connections
• Preview all views - use open-view for each defined view
• Verify syntax - use Context7 MCP if uncertain about syntax features
• Check for compilation errors in VS Code Problems panel
• Run likec4 start locally to ensure diagrams render

Parent Context Validation

Critical requirement: Every view MUST explicitly include its parent/surrounding element.

For detailed context requirements, see PARENT_CONTEXT_REFERENCE.md

Context Checklist for Views

• C1 Context view: System boundary clearly shown? External systems included?
• C2 Container view: System boundary shown? Containers appear WITHIN system?
• C2 Container view: Neighboring containers shown? (include -> vault.* and vault.* ->)
• C3 Component view: Parent container boundary shown? Components appear WITHIN container?
• C3 Component view: Neighboring containers shown? (include -> service and service ->)
• Deployment Zone view: Zone container shown? VMs appear WITHIN zone? Parent environment included?
• Deployment VM view: VM container shown? Instances appear WITHIN VM? Parent zone included?
• Dynamic/Sequence view: Initiating actor shown at start? Causality clear?

Common mistakes:

• ❌ C3 view without parent container boundary
• ❌ C2 view without system boundary
• ❌ Deployment VM without parent zone
• ❌ Sequence without initiating actor
• ✅ Every view contextualized by showing what contains it

Output

Comprehensive validation report identifying:

• Broken or invalid references
• Syntax errors or warnings
• Missing or incorrect metadata
• Views that don't render as expected